Engine



March 10, 1936. 3 MURPHY I 2,033,350

ENGINE] Filed Oct. 20, 1951 4 Sheets-Sheet 1 a0 a4 59 I Mayes u/phy March 10, 1936. M. J. MURPHY 2,033,350

ENGINE I Filed Oct. 20, 1951 4 Sheets-Sheet 2 INVENTOR Moyes J. Murphy ATTORNEY I March 10, 1936. M. J. MURPHY 2,033,350

ENGINE i Y Filed Oct. 20, 193; 4 Sheets-Sheet (5 ill INVENTOR Maya: J Murphy A TTORNE YS MarchlO, 1936. J. MURPHY ENINE Filed 001;. 20, 1931 4 Sheets-Sheet 4' m7 a5 a2 /25 w w 02 w r m mm w Md w n. 1 me Patented Mar. 10, 1936 UNITED STATES ENGINE Application October 20, 1931. Serial m. 569,90!

6 Claims. (or. 123-21 My invention relates to engines of the internal combustion type and particularly to engines designed to operate on relatively heavy fuels such as heavy hydrocarbon oils. Such engines are 5 usually termed Diesel engines inasmuch as they operate in accordance with the cycle first proposed by Dr. Rudolph Diesel andmy engine particularly relates to that type of engine which v operates on the solid injection principle. The

10 solid injection principle is distinguished from the air injection principle in that the fuel is injected directly into the cylinder by means of pressure upon the liquid fuel itself and without admixture of air and without depending upon 10 compressed air for injection.

Such engines have been built in great quantities during past years but all of them have been faced with the diflicult problem of starting. An engine operating in accordance with the Diesel cycle has a relatively high compression pressure and an engine of any size, particularly one designed for automotive work, has substantially been incapable of being rotated for starting purposes by an operator or by any of the usual 25 electric or other common starting mechanisms. An air injection engine has available usually a relatively large supply of compressed air under a relatively high pressure so that a supplemental air engine serves admirably as an auxiliary startingdevice while with a solid injection engine such as the one described herein, there is not available any satisfactory auxiliary mechanism for starting nor is there any large supply of air under pressure which is available to operate such auxiliary devices. a It is considered advantageous to start such solid injection engines either by hand cranking or by means of a relatively small electric motor such as now commonly used -for starting purposes in the automotive field. It is therefore an object of my invention to provide an engine operating on the Diesel cycle and with solid fuel injection but which can easily be started by an operator or by the customary electrical or a similar starting device.

Another object of my invention is to provide means for facilitating the starting of 'a solid injection Diesel engine under cold conditions when the temperature of the engine is so low as to hamper the production of auto-ignition of the fuel despite the relatively high compression ordinarily utilized. e i 4 Another object of my invention is to provide 55' a Diesel engine which is capable of operating lustrative arrangement.

quite slowly without fear of carbonization or fouling A further object of my invention is to provide a Diesel engine which is substantially no heavier than a comparable gasoline engine of similar 5 horsepower and characteristics.

A further object of my invention is to provide a control mechanism for a Diesel engine which will permit not only of proper operation of the engine with heavy fuel on the Diesel cycle but also upon the Otto cycle using a light fuel such as gasoline.

' A further object, of my invention is to pro- .vide an engine capable of operating either on a light hydrocarbon such as gasoline upon the Otto cycle or on a relatively heavy fuel such as Diesel oil upon the Diesel cycle.

- The foregoing and other objects are attained in the embodiment of the invention shown in the drawings, in which Q Figure 1 is a cross-section on a vertical transverse plan through the first cylinder of an engine constructed in accordance with my invention.

Figure 2 and Figure 3 together show the engine of my invention in side elevation, certain portions being shown in cross-section on vertical planes.

Figure 4 is a rear elevation of an engine constructed in accordance with my invention, certain portions of the mechanism being disclosed diagrammatically and in cross-section.

In its preferred form the engine of my invention comprises an internal combustion mechanism designed to operate generally on the solid injection Diesel cycle and combined with means for permitting the operation ofthe engine, particularly for starting and slow running, on the customary Otto cycle using gasoline or comparable light hydrocarbon as a fuel, together with mechanism which precludes unwarranted 01' harmful operation of the engine upon a combined cycle:

Although the engine of my invention is susceptible to various difierent uses and is susceptible to modification for use in different environments,

I have disclosed herein a typical form of engine primarily designed for use in a tractor as an il- This engine comprises a crank case 6,which at its rearward end is indirectly carrled by a support-1 for a cross shaft 50,

forms a continuation of the crank case and itv self is designed to be bolted or otherwise secured to the clutch housing and transmission case, not

shown, of the tractor in accordance with customary fashion. The crank case is substantially a box rectangular in cross-section and is preferably machined on all four side faces to receive associated parts and' closures for apertures formed in the crank case.

These apertures include a sump aperture I I on the lower face of the crank case which is closed by a sump pan |2 usually of cast metal and extending to the rear of the crank case to carry the supports 1 and 8. The sump pan l2 provides an oil tight closure for the lower portion of the crank case and likewise forms a mounting for an oil strainer l3 in the customary fashion. The sides of the crank case 6 are provided with apertures l4 and I6, serving as hand holes, which are closed by cover plates I1 and I8, respectively, held in place by any suitable means such as bolts l9. Spanning the crank case 6 transversely at suitable intervals are webs 2| acting as mountings for the main bearings 22 of the engine. The main bearings are preferably formed with their upper caps 23 integral with the crank case webs 2| while the lower caps 24 are held in place by through bolts 26.

Rotatably mounted in the aligned main bearings 22 is a crank shaft 21 of the customary four throw five bearing type. The crank shaft is provided opposite each check with a detachable counter weight 28 held in place by suitable bolts and nuts 29*whi1e between adjacent checks of the crank shaft connecting rod pins or crank pins 3| are provided. Since all of the cylinders of the engine are substantially identical with the possible exception of minor details the description of but one of them will suflice. Each of the crank pins 3| serves as the mounting for a connecting or pitman rod 32, at its lower end provided with an integral upper bearing cap 33 and a separable lower bearing cap 34 held to the upper cap by means of through bolts and nuts 36. Preferably the crank shaft 21 is drilled suitably to provide an oil passage 35 which communicates periodically during the rotation of the crank shaft with a drilled passage 31 extending thru'a web of the connecting rod 32 from the crank pin 3| to a wrist pin 38 piercing a continuous band 39 forming an eye in the'extremity of the connecting rod 32 and likewise mounted to rotate in the bosses 4| of a piston 42.

Upon rotation of the crank shaft 21 and through the medium of the connecting rod 32 the piston 42 is reciprocated within a removable liner 43 providing the cylinder bore of the engine. The liner is suitably pressed into and held by the cylinder block casting 44 mounted on the crankcase 6 and located thereon by virtue of the fact that the through bolts 26 pass through suitable passages in the cylinder block 44. The sleeve or liner 43 at its upper end is externally flanged as at 46 to fit in a corresponding groove cut in the cylinder block 44 and between its ends abuts a rubber gasket 41 or any other suitable packing means for preventing leakage past the lower seat of the sleeve on the cylinder block 44.

" The cylinder block is preferably formed with a wall 48 which encompasses all of the cylinder liners 43 and is spaced therefrom to provide a Y water jacket 49 for cooling purposes.

Mounted on .the cylinder block 44 is a cylin ,ing between the cylinder block and the cylinder head serving as a seal to prevent leakage. The contour of the throat member 54 is such that the piston 42 at the upper point in its stroke approaches very closely to the surface of the member 54 and leaves but a slight compression space,

such as 58, between the top of the piston and the lower surface on the throat member 54.

Furthermore, the throatmember is restricted in bore to a diameter substantially one half of the bore of the diameter of the engine cylinder but is againwidened to meet the bore of the combustion chamber 53.

In order to facilitate the combustion in the engine, I take advantage of the tendency of the piston at the upper portion of its stroke to dislodge a very large volume of gas from the compression space 58 through the relatively narrow throat 59 of the throat member 54 into the combustion chamber 53. To this end the piston 42 is provided with an axial bore within which a stud 60 is seated and is held by a locking device such as a nut 6|. The stud 60 at its upper end is flared to provide a disc 62, the upper surface 63 of which is concave to follow the general contour of the combustion chamber 53 which may be described as being of lens shape. The portion 64 on the periphery of the disc 62 is irregular or is serrated with the serrations lying in spaced helical paths after the fashion of a helical toothed gear, for the purpose of causing a helical swirl of the matter discharged from the interior of the cylinder by the piston in the upper portion of its stroke and-for causing a whorl around the entire interior surface of the combustion chamber 53 during the completion of the compressor stroke.

The cylinder head 5| is provided with a water jacket space 66 suitably surrounding the combustion chamber 53 and communicating with the water jacket 49 in the cylinder block 44. Water from the jacket 66 is carried through a cored passage 61 in a housing 68 fitted on the cylinder head to a conduit 69 provided therein and leading to a radiator 1| presently to be described.

The combustion chamber 53 is placed in communication with the incoming gas and with outgoing gas at suitably timed intervals by means of an inlet 'valve 12 and an exhaust valve 13. The inlet valve 12 is of the customary poppet type and controls communication between the combustion chamber 53 and an inlet duct 14 while theexhaust valve 13 is of a similar poppet type and controls communication between the combustion chamber 53 and an exhaust duct 16. Each of these valves is maintained on its seat by a coil spring 11 surrounding a valve guide 18 pressed into the cylinder head 5|. The inlet valve 12 is actuated by a rocker arm 19 project-- ing from a shaft 80 rotatable in pedestals 8| and 82 secured to the cylinder head 5|. valve is similarly actuated by means of a rocker arm 83 formed integrally with a sleeve 84 bearing upon the shaft 80.

The exhaust The shaft 80 likewise carries a rocker arm 80 terminating in an adjusting mechanism 81' at the upper end of a push rod 88 passing through a guide 83 mounted in the cylinder head and the crank case 6. The exhaust valve I3 is similarly actuated by a rocker arm Ill carrying an adjusting device 92 at its extremity'which bears on the upper end of a push rod 93 extending through a guide 94 similarly held between the cylinder head 5i and the crank case 6. At their lower ends the push rods 88 and 03 terminate in rollers 90 and 97 respectively which bear on followers 98 and 99 respectively interposed between the rollers and earns IOI formed on a cam shaft I02 extending longitudinally through the crank case 0 and mounted in suitable bearings I03 therein. Access to the followers and to the cam shaft is through a cover plate I04 mounted on the machined side face of the crank case 6. The arrangement is such that the followers 98 and 99 are mounted concentrically on a through shaft I06 which extends longitudinally of the engine and is carried by bored clamps I0I fastened to the crank case 6 by bolts I08.

Mounted between the push rod housings and 94 is a fuel pump I I I of any standard kind which is secured by studs H2 to the upper side of the crank case 6 and is provided with a depending plunger II3 adapted to contact a follower II I carrying a roller I I5 bearing on a cam I I6 on the cam shaft I02. The follower H4 is preferably provided with a bearing lug III in contact with the plunger II3. The follower IE0 is provided with an eccentric ring I I8 which encompasses an eccentric IIQ formed on the longitudinal shaft I06 so that upon rotation of the shaft I06 the followers 98 and 09 are not disturbed, but the follower II is moved transversely of the engine so that the cam I I6 is effective upon the depending plunger H3 of the fuel pump III at different times during its cycle of rotation. In this fashionby suitably rotating the shaft I06 the time of operation of the fuel pump III is varied. The amount of fuel discharged by the pump is varied from zero to maximum by a rod I20 moving longitudinally of the engine.

The fuel pump receives the liquid fuel for the engine through a suitable arrangement of ducts I2I and discharges through a conduit I22 into a nozzle I23. or injector of any standard kind which is mounted in a suitable bore I20 in the cylinder head SI so that the jet of liquid fuel issuing from the nozzle extends transversely of the combustion chamber 53 and is suitably merged with air compressed therein at the end of the compression stroke. Access to the fuel nozzle I23 and to the fuel pump III is obtained by removing a cover plate I26 which is fastened\. to the machined side of the cylinder block M and of the cylinder head 5|.

The cam shaft I02 for actuating the push rods 88 and 93 and also for actuating the fuel pump III is driven through appropriate gearing. At its forward end the cam shaft carries a gear I3I which is twice the diameter of a crank shaft gear I32 with which it meshes. Due to the ratio of the diameters of these gears the speed of the cam shaft I02 is exactly half the speed of rotation of the crank shaft 21 which isproper for. a four stroke cycle engine of the type described.

The cycle of the engine is in accordance with the usual Diesel cycle and with the so far described the engine is capable on. the suction stroke of inducing air to flow in through the intake valve, of subsequently compressing the downstroke of the piston 42.

air taken in during which time the intake valve is closed, and, adjacent the upper portion of its stroke of receiving a charge of combustible fuel from the fuel nozzle I23, of subsequently moving on a downward stroke under the influence of the expanding products of combustion and. finally discharging such products of combustion through the appropriately opened exhaust valve.

Although an engine operating in accordance with the described cycle is perfectly satisfactory for relatively heavy and medium duty it is very difflcult to start manually and is not particularly susceptible to light load or slow running. In order to achieve the objects of my invention, I provide means for operating the engine upon a relatively light hydrocarbon fuel such as gasoline and not on the Diesel cycle but on another cycle,

usually the Otto four stroke cycle. As is well know, the compression in accordance with the Diesel cycle is relatively high while the compression in accordance with the Otto cycle is relatively low and to afford a difference in clearance volume in the cylinder in order to provide for the necessary difference in compression pressures, I provide a means for augmenting the combustion chamber 53 when the engine is to be run in accordance witlr the Otto cycle.

To this end, the engine is built with a means for lifting the intake valve 12 and holding the intake valve I2 open during the operation of the engine in accordance with the Otto cycle. A longitudinal shaft I33 is held by the clamps I01 and is provided at spaced intervals along its length with cams I34. Each cam is designed when properly rotated, usually by hand, to abut a roller I36 on an extension of the cam follower of the intake valve. rotated clockwise, as viewed in Figure 1, the cam I34 abuts the roller I36 and causes the follower 99 to rotate about its concentric axis on the shaft I06 thereby lifting the cam follower 96 and the push rod 08 independently of the cam shaft I02 to hold the inlet valve I2 open thereby establishing continuous communication between the combustion chamber 53 and the intake duct I4.

In order that a proper amount of the inlet duct It will be utilized to augment the combustion chamber 53 and to provide an auxiliary combustion chamber for operation on the Otto cycle I preferably terminate the intake duct It adjacent the upper face of the cylinder block 03 by providing a valve seat I37. Adapted to operate on this seat is a poppet valve I30 provided with a stem I39 operating in a guide IEI secured in a pocket I32 formed'in the cylinder block 40. The valve I38 is normally held on its seat by means of a relatively light coil spring I03 which however, is ineffective against vacuum existing in the inlet duct I0 on the suction or In other words, the valve I38 is an automatic valve to the inlet duct II and is consequently capable of closing during the time, any pressure approximating atmospheric pressure is present in the duct It. The pocket I42 communicates with a carburetor I40 which is capable of providing a combustible mixture of air and light fuel such as gasoline to the pocket I02 from which the combustible mixture flows through the passage around the valve I38 to the inlet duct I4 and thence to the combustion chamber 53. I

Under operation on the Otto cycle, the main intake valve I2 is open, the valve I38 serves as an automatic inlet valve for the engine and When the shaft I33 is I the inlet duct 14 and the combustion chamber 53 are combined to present the proper volume. so that the compression pressure effected by the piston is proper. Operation on the Otto cycle is at a compression pressure such that auxiliary ignition mechanism is necessary and for this reason I provide a standard spark plug "I in the cylinder head 5I, the spark plug being suitably energized in proper time relationship by means of a lead I12 extending to a magneto I13 of a standard kind mounted on the upper face of the crank case 6 and carrying a gear I14 which is driven from the cam shaft gear I3I by means of an intermediate gear I16.

X During operation on the Otto cycle the spark plug I1I is suitably energized at proper intervals and produces combustion of the explosive mixture in the augmented combustion chamber 53 while during operation on the Diesel cycle the spark plug may or may not be energized depending upon the particular design of the mechanism and in any event, is not subjected in any way or manner to the excessive pressures and temperatures existing within the combustion chamber 53 during operation on the Diesel cycle since then only relatively cold air is present in the inlet duct 14. There is therefore no difficulty experienced in operation when a spark plug is positioned as indicated herein.

To control the position of the valve I38 which is operative during operation of the engine on the Otto cycle but is inoperative during the operation of the engine on the Diesel cycle I preferably mount a bell crank I15 on a pivot bracket I11 secured to a cover plate I18 fastened to the side of the crank case 6 and the cylinder block 44. The bell crank is provided with one arm I19 adapted to abut the end of the valve stem I39 and is likewise provided with another arm I8I adapted to be acted upon by a cam I82 fastened on a longitudinal shaft I83 passing along the side of the engine and held in place between the cylinder plate I18.

When the engine is to be operated on the Diesel cycle, the shaft I83 is rotated so that the cam I82 contacts the arm I8I of the bell crank lever and rotates it about its pivotal mounting on the bracket I11 so that the arm I19 contacts the valve stem I39 and against the urgency of the spring I43 holds the valve I38 off its seat so that fluid from the pocket I42 passes around the valve substantially unobstructedly and through the inlet duct 14 to the combustion chamber 53. Under operation on the Otto cycle however, the shaft I03 is rotated so that the cam I82 is out of contact with the arm NH, and the bell crank lever I15 under the urgency of gravity or a spring, not shown, swings out of the path of operation of the valve stem I39 and the valve I38 then responds to variations in pressure between the pocket I42 and the inlet duct 14 under the control of the spring I43.

In order that the various controlling shafts of the engine may be operated I provide a con trol linkage as shown in Figure 4. In this figure, the carburetor I44 is shown as mounted on an air cleaner I84 having an air inlet I85 and an air outlet I88 communicating with the pocket I42. A transverse wall I81 in the air cleaner prevents cominunication between the inlet I85 and the outlet I86 except through the carburetor I44 when a butterfly valve I88 is closed. Air from the interior of the air cleaner I84 flows into the carburetor I44 through an inlet, tube I45, is carblock 44 and the removable cover bureted, and flows through an outlet tube I 50 into the pocket I42. the inlet I85 and the outlet I86 shunting the carburetor, is permitted when the valve I88 is open. The butterfly valve is mounted to turn with the shaft I83 and is arranged to be closed, thereby rendering the carburetor effective, when the shaft I83 is in a position to be ineffective on the valve I38. However, when the butterfly va-lve I88 is opened, thereby by passing or shunting the carburetor, as in operation on the Diesel cycle, the shaft I83 is effective to lift or to disable the valve I38.

The shaft I83 carries a lever I89 connected by a rod I90 to one arm I9 I of a. bell crank provided with an enlarged pivot boss preferably journaled in the rear face of the cylinder block.

The other arm I92 of the bell crank is connected by a rod I93 to a starting lever I94 preferably fixed on the extremity of the shaft I33. When the shaft I83 is in position for operation on the Otto cycle, the described linkage causes the shaft I33 to be in such a position that the cam I34 engages the roller I36 and holds the intake valve 12 off of its seat. This is the starting position. When, however, the starting lever I94 is moved to run position, as shown in Figure 4, the shaft I33 is rotated to remove the cam I34 from effect on the roller I36 and permits the valve 12 to be actuated solely in response to the cam shaft I02. The lever I94 when moved to run position forces the rod I93 to rotate the bell crank so that the rod I90, through the medium of' the lever I89 rotates the shaft I83 to open the butterfly valve I88 and to disable the valve I38.

The rod I is moved axially to vary the injection of fuel as to amount by means of mechanism which is partially dependent on the posi-: tion of the starting lever I94 so that in start position the injection of relatively heavy fuel is precluded. The fuel pump III is ordinarily responsive to a governor of any suitable kind which is effective to move the shaft I20. Also effective on the shaft I20 is a bell crank I95 mounted to pivot about a .horizontal transverse axis and carrying a compression spring I80. Adapted to act on the spring I80 after overcoming considerable initial lost motion is a plunger I96 mounted pivotally on a lever I91. The lever 'is fulcrumed on a pin I98 projecting eccentrically from the enlarged central boss of the bell crank havingthe arms I9! and I92. The lever I91 is connected by a rod I99 to a speed regulating lever 280 fixed on the shaft I06.

When the lever I94 is in run or Diesel cycle position, the location of the bell crank is such that the plunger I99 contacts the compression spring I80. Subsequent movement of the lever 200 compresses and releases the spring I80 to vary the resistance which must be overcome by the governor in moving the shaft I20 to regulate the speed of the engine. Since the lever 200 is on the shaft I06, the time of injection of the fuel is varied in accordance with the'amount of fuel injected. Thus, as the shaft I06 is rotated toward fast position, the follower H4 is projected to give an earlier actuation of the plunger II3 by the cam IOI.

When the lever I94 is in start position, the pivot pin I98, being eccentrically mounted, is lifted, and the plunger I96 is raised from contact with the spring I 80 a sufficient distance that no matter in what position the lever 200 is placed, the spring I80 is not compressed and Communication between the shaft I20 must remain in position to prevent injection of fuel by the pump Ill.

The engine is likewise provided with a suitable mechanism for circulating cooling water through the jackets 49 and 66 and likewise through the outlet duct '59. of the crank case 6 isa plate 20l which not only forms a mounting for a timing gear cover 202 but likewise forms part of the support for the radiator II which additionally is mounted on an extension 204 secured to the crank case at its forward end. The extension 200 forms the mounting for a shaft 200 at its forward end 20! designed to receive a hand crank and at its rearward end provided with a uni-directional clutch 208 for engagement with the forward end 209 of the crank shaft 21 for cranking the engine manually.

The radiator H which rests on the housing 204 and is additionally supported by the plate 20| comprises an upper tank 2| i into which the water outlet 69 discharges. The upper tank is provided with a filler cap 2l2 which is in the nature of a poppet valve normally held closed by a spring 2| 3 surrounding a telescopic stem 2| 0 so that to fill the radiator, it is merely necessary to depress the cap 2l2 against the urgency of the spring 213 and to swing the telescopic mounting 2! about its point of pivotal attachment 2| 6. Suitable tubes extend from the upper radiator head 2!! to a lower radiator head, integral with the support 204, from whence the cooling water is returned to the engine. Interposed between the upper header and the lower header is a cooling fan 22! preferably of the sirocco type which induces an axial flow of air which is discharged tangentially over the cooling tubes of the radiator. Spanning the sirocco fan 22| between the upper tank 2 and the lower tank 205 is a spider 222 on which a rotatable shutter 223 is mounted. In one position of the shutter, the apertures, therein are in registration with the apertures in the spider and free air flow is permitted whereas, in a rotated position of the damper, its apertures are out of registration with the apertures in the spider and no air flow is permitted.

The sirocco fan 22! is mounted for torsional resiliency on the forward end of a fan shaft 22% carried in bearings 22? and 228 secured in a pump housing 229 fastened to the forward face of the timing gear cover 202. Between the bearings 221 and 228 is fastened the impeller 23l of a water pump which withdraws the cooling water from the lower tank 20d of the radiator and discharges the cooling water into the water jacket 69. Also mounted on the fan shaft 226 adjacent its rear end is a governor 230 of any suitable design which is effective to move the shaft I20 axially to regulate the volume of fuel pumped, as previously described.

In accordance with my invention, the engine is initially started by throwing the control lever 200 to start position and either utilizing a hand crank on the shaft 207 or an electric Mounted on the forward end shaft I20 longitudinallyso that the pumps III are incapable of discharging any fuel oil.

When the engine is started thus on the Otto cycle, using gasoline, it is relatively easily cranked and quickly comes up to a normal operating temperature under a relatively light load. As soon as the engine is operating satisfactorily the lever I94 is moved to run position which is effective to place the valve I38 in inoperative, open position, to de-energize the spark plug I'll, to open the butterfly in the air cleaner, to translate the shaft I20 longitudinally so that the fuel pump HI injects fuel oil into the combustion chamber 53 at the proper time, and likewise rotates the shaft I33 so that the main inlet valves 12 are solely under the control of the cam shaft I 02 which operates them in proper sequence and in conjunction with the operation of the remainder of the engine. At any time during the operation of the engine the cycle can be changed from Diesel to Otto for light running and for idling thereby avoiding fouling and carbonization of the combustion chamber and valves and providing for a simple control under light load conditions. 0n the other hand, the engine can at any time be changed over to operation on the Diesel cycle which is suitable for heavy use and for continuous heavy load running.

It is to be understood that I do not limit myself to the form of the engine shown and described herein, as the invention, as set forth in the following claims rality of forms.

I claim:

1. A four-stroke cycle engine comprising a main chamber, an auxiliary chamber opening into said main chamber and opening to the atmay be embodied in a plu-' mosphere, a valve for controlling communica- I tion between said main chamber and said auxiliary chamber, an inlet valve for controlling communication between said auxiliary chamber and the atmosphere, and means for mechani cally operating said valve in time with the operation of said engine while holding said inlet valve in open position and alternatively holding said valve in open position and releasing said inlet valve to operate in time with the operation of said engine.

2. A four-stroke cycle engine adapted to operate on the Otto cycle and on the Diesel cycle comprising a main chamber, an auxiliary chamber opening into said main chamber and to the atmosphere, valves for controlling communication between said auxiliary chamber and said chamber and between said auxiliary chamber and the atmosphere, respectively, and valve mechanism for operating sa'id valves in time during the operation of said engine on both the Otto cycle and the Diesel cycle so that there is a flow of air from the atmosphere through said auxiliary chamber to said chamber for every fourth stroke of said engine.

3. A four-stroke cycle engine comprising a main chamber, an auxiliary chamber, a valve operating in time with said engine for controlling flow between said auxiliary chamber and said chamber, means for holding said valve in open position, an inlet valve between said auxiliary chamber and the atmosphere adapted to operate in time with said engine, and means for holding said inlet valve in open position.

4. A four-stroke cycle engine comprising a main chamber, an auxiliary chamber communicating therewith, a duct communicating with said auxiliary chamber and with the atmosphere,

a carburetor opening into said duct, means for selectively opening said duct to said carburetor or to the atmosphere, an inlet valve for closing communication between said duct and said auxiliary chamber periodically during the operation of said engine, means for disabling said inlet valve, a valve for closing communication between said auxiliary chamber and said chamber periodically during the operation of. said engine and means for disabling said valve.

5. A four-stroke cycle engine comprising a main chamber, an auxiliary chamber communicating therewith, a duct communicating with said auxiliary chamber and with the atmosphere,

a carburetor opening into said duct, means tori selectively opening said duct to said carburetor or to the atmosphere, an "inlet valve for closing communication between said duct and said aux-- iliary chamber periodically during the operation 0! said engine, a valve for closing communication between said auxiliary chamber and said chamber periodically during the operation of said' engine and means for alternatively disabling said valve and said inlet valve.

6. A four-stroke cycle engine adapted to perate on the Otto cycle and on the Diesel cycle, comprising a main chamber, an auxiliary chamber opening into said main chamber and 'to the atmosphere, a first valve for controlling communication between said chamber and said auxiliary chamber, an inlet valve for controlling communication between said auxiliary chamber and the atmosphere, and means for operating said valves so that said auxiliary chamber serves as the sole air inlet passage to said chamber during operation of said engine on the Diesel cycle and for holding said first valve open during operation: of said engine on the Otto cycle so that said auxiliary chamber then serves as an additional combustion chamber.

MOYES J. MURPHY. 

